DSA's catchment area isn't tiny, as LA suggests. However, most in the catchment area have 4 or 5 alternative airports to choose from. Very few are inconvenienced by flying from somewhere else. I'm a Sheffielder who regularly flies to and from Alicante who'd love to fly from DSA but the price and the (currently early morning) flight times with Flybe and TUI make me look at EMA, MAN and even Liverpool.